A federal court ruling has revealed that the U.S. Department of Justice has routinely been monitoring the locations of people through their cell phones, without probable cause, and in secret.

Your shiny new GPS-enabled cell phone can be used to track you in real time by government authorities, even when you supposedly have it disabled. The only way to prevent it is to shut the phone off, which makes it not very useful.

The Electronic Frontier Foundation argued in federal court, in the first such case to actually have opposition show up, that the Fourth Amendment requires a search warrant for such surveillance.

The government has tried to justify this gross expansion of its authority by combining two surveillance statutes, neither of which authorize cell phone tracking on their own. As EFF explains in its brief, there is no support anywhere for this argument — not in the statutes’ language, nor in legislative history, case law, or academic commentary. Indeed, it contradicts the government’s own electronic evidence manual. “It’s as if the government wants the court to believe that zero plus zero somehow equals one,” said [staff attorney Kevin] Bankston. — Electronic Frontier Foundation

EFF further states that the federal court ruling indicates that prior authorizations were granted by the courts without the prosecution even establishing probable cause to believe that a crime has been or will be committed, a critical legal standard under U.S. law.

It’s partly because of things like this that I’ve had my phone off for most of the last week, only turning it on to check messages or make a call. Not that I’m a criminal, far from it. But the government has no right or reason to track me in real time. If they are only using this power against criminals, then showing probable cause in court in order to get a warrant should be easy enough. Otherwise, anybody could be tracked at any time for any reason — or no reason at all. And America should not be that sort of police state.